I don’t see eSIM option on my iPhone 11

Either you have a version of the iPhone 11 that does not support eSIM......or......your carrier does not support eSIM.

Tap Settings > General > About > Model Number

Tap directly on the Model Number and another number will appear.....examples.....A2111.....A2221.....A2223

Post back with the model number that you see

Contact your carrier for help. They have to support eSim.